Problem to Add name in ration card in Kangayam Tamil Nadu

Respected sir / mam I would like to add my name and my brother name in ration card. I don't have a another ration card. My name and my brother name had in our old ration card. But we change the city after year so we submit the old ration card and have got a new one but they didn't add my name and my brother name. Then we went a taluka office and wrote a letter to the officer for add my and my brother name in ration card, and submit our certificate proofs. Although we submit the proof they didn't add our name. Thatswhy When I was 6 My father was left from us and we don't know where he was been. My mother got a second marriage after a year. We accept him as our father but we didn't change our Father's name in our school certificates. This is the problem to add our name in ration card. They said they didn't add our name because we are not our step fathers child. Then they said go and get a sign and proof of my father's id from my father. If i get that sign and proof Afterthat they will add our name. But no chance to get his sign because we don't know where he is then how can we get a proof. I don't know what I do to add our name in our ration card. pls help me and suggest me. Thanking you